1. Field of the Invention
This specification relates to a butterfly valve, and particularly, to a butterfly valve capable of controlling fluid flow according to rotation of a disc disposed in a valve.
2. Background of the Invention
Generally, valves are installed at part of a piping system formed by pipes, etc. which form a fluid path, and serve to control fluid flow to be stopped or to be maintained.
A type of the valves, a butterfly valve is configured to open and close a flow passage according to a rotation of a disc installed in a valve body. More concretely, a sealing member is disposed to block a gap between an opening/closing member (disc) and a housing, so as to prevent a fluid from leaking to the gap in a state that fluid flow has stopped.
The sealing member is installed at the housing with a contacted state to the opening/closing member with an initially-set pressure. However, while the disc is rotated, the disc and the sealing member come in contact with each other. The disc or the sealing member may be abraded due to repeated contacts therebetween.
Accordingly, may be considered a method for preventing interference due to contact between the disc and the sealing member.